My 1st Build & More questions than answers.

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marlton67
Posts: 9
Joined: Wed May 16, 2018 3:04 pm

My 1st Build & More questions than answers.

Post by marlton67 »

Hi Guys,
I know very little about but have taken the plunge & decided to Build an Ant-weight robot for:
AWS55 - 30th June 2018 - Dunchurch Village Hall.
Now never have built a Robot & not knowing a lot this could be a tall order,
So 3 Questions?

I Want to build a 2 wheeled pusher (Ramp-Ant). Parts on order are:
(I am not expecting to win anything, Just want to compete)

2 x https://www.ebay.co.uk/itm/10A-Bustophe ... 2749.l2649
1 for each wheel? (is this correct?) Q1:
Also I have received it with no details which wire goes where?
Image
Q2: Is there a diagram i can access on the web?

1 X Lemon RX with pins & without (in case I blow one up)
https://www.ebay.co.uk/itm/Lemon-RX-6-C ... 2749.l2649
Image

2 x Motors (DC 6V 500RPM Micro Metal Gear N20 speed ratio 1:30 w/ shaft length 3*10 DT)
These I think I understand!!

1 x Spektrum DX6i Transmitter & Devo 7E (from China will see how long it takes)?

1 x Nano Tec 300 2s 7.4v and Blance Charger + Bag.

Main aim at the moment is to get the wheels motors to work via my DX6i. Q3: am I missing anything?

Any help will be very welcome
Regards Ian
marlton67
Posts: 9
Joined: Wed May 16, 2018 3:04 pm

Re: My 1st Build & More questions than answers.

Post by marlton67 »

This Photo should sum up my Questions hope I have it right?
Image
https://imgur.com/a/cIBm5N3
https://imgur.com/a/cIBm5N3
BobHill452
Posts: 8
Joined: Sat Jan 20, 2018 2:26 pm

Re: My 1st Build & More questions than answers.

Post by BobHill452 »

Hi there, Welcome!

Looks like your on the right track with the things you've got. You'll want some wheels and of course something to build the chassis out of. You can buy wheels that fit the D shaft. Something like this is specially made to fit the shaft: https://www.pololu.com/search?query=wheels&x=0&y=0

If you go to this ebay listing:
https://www.ebay.co.uk/itm/2x-10A-RC-Br ... SwrtVZrkx8
And look at the last picture along it contains a wiring diagram to help you see how to wire the ESC up. I know the model in the listing isn't the same as the one you have but the wiring is the same.


You'll need (well it would be better to but not essential) to modify the wiring so that both ESC are turned on and off by one switch. Some people just remove the switch(es) on each board and then connect the ends of the wires together where the switches used to be so they are 'always on'. You would then put a switch in series with the battery and control the on off from there.

You'll also want to set up the wiring so both ESC are pluggged into the battery (imagine a Y shape with the two + wires going into one wire then (via the aforementioned switch) to the + of the battery and from the - side a single wire coming out which then splits into 2 wires one going to the - of each ESC.

When it comes to the three colour wire connector this would go to your receiver. This wire provides power at a safe voltage for your receiver and also receives signal from the receiver which the ESC then turns into motor speed and direction. Check this site for the colour coding of the wires:
https://www.pololu.com/product/1046/faqs

You'll want to plug the three colour wires into the receiver. However I believe that for one of the ESC you will want to cut the red power line. This is because both ESC have what is called a BEC on them. This is a battery eliminator circuit or basically a device which turns the 7.4v from the battery into a safe 5v which the receiver can handle and not be blown up by. It is my understanding that if you have two BEC acitve, they can interfere with each other and cause issues. Hopefully someone else can confirm i've got that bit right, but basically we only want one ESC to use its BEC to power the receiver and we can achieve this by not using the +/power line from one of them.

You're right about it being one ESC per wheel.

A few other tips.

Make sure you're motors aren't touching when you power up as this could lead to a short circuit and some blown up electronics. Some have found those cheap motors have issues out of the factory so i'd suggest just test them with a battery first to see that they run fine.

Also those ESC have a little switch on them which turns on/off a funny braking feature which you don't really want enabled because it makes driving impossible. basically if you get it wired up and find it difficult to get the motors to reverse then just turn everything off and flip the little switch on the board and try again.

Hope that helps.
BobHill452
Posts: 8
Joined: Sat Jan 20, 2018 2:26 pm

Re: My 1st Build & More questions than answers.

Post by BobHill452 »

marlton67
Posts: 9
Joined: Wed May 16, 2018 3:04 pm

Re: My 1st Build & More questions than answers.

Post by marlton67 »

Thanks guys well explained Will attempt to get a motors working this week.

The video is very helpful have to sit down and plod thru this again thanks.
Regards
Ian
T_Y
Posts: 153
Joined: Thu Mar 15, 2018 12:51 am
Location: York

Re: My 1st Build & More questions than answers.

Post by T_Y »

Hi there! I'm running the same setup in one of my bots. If it helps, here is an adapted wiring diagram for just the drive element (Brown is signal, Red is power, Black is ground), assuming you are mixing the elevator and aileron channels on the transmitter (I'm using a Devo 7e for this):

Image
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marlton67
Posts: 9
Joined: Wed May 16, 2018 3:04 pm

Re: My 1st Build & More questions than answers.

Post by marlton67 »

Hi excuse my idiocy but:
"assuming you are mixing the elevator and aileron channels on the transmitter"
Would this mean I could run both drives off of 1 stick? This would be great!!
I thought I would use 1 stick for each of the 2 wheels!
If it was possible to mix, could this be done on my DX6i ? (as the devo 7e is still on the boat from China so may arrive after the event!)

Regards
ian
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DieGracefullyRobotics
Posts: 152
Joined: Mon Apr 02, 2018 7:39 am

Re: My 1st Build & More questions than answers.

Post by DieGracefullyRobotics »

Hey Ian,
The DX6i is fine for ants (and most robots, I drove my heavyweight with one) and has mixing. Stick "DX6i mixing" into YouTube for a ton of tutorial videos on how to do it, plus a load of other handy tips.
Dave.
Dave
Die Gracefully Robotics - Barely Even a Proper Team.
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